The present invention relates generally to a system for improving the equalization of machine component wear and overall utilization of wide abrasive belts utilized in but not limited to surface abrading machines, and more particularly to a use prompter/monitor system for use in combination with such machines wherein an array of individual monitors and/or sensors is employed. Each sensor monitors one discrete segment of the transverse width of the belt, with the activity of each segment being compared to all others in the array. The system of the present invention serves to monitor the extent of usage across the entire width of the belt and machine, and at the same time, serves to prompt the operator when certain segments are being overly utilized or alternatively are being under-utilized. Since the lifetime of a wide abrasive belt and certain machine component wear relates directly to the most heavily utilized segment, it serves an economic advantage as well as an environmental benefit to equalize belt usage and wear as much as practicable.
In the operation of many machines, and particularly wide-belt sanders, the recommended and preferred practice is to endeavor to have the workpieces or product being surfaced be substantially evenly fed across the working width of the machine. Because of variations in the application of these machines to a variety of different workpieces and due to individual operator preferences, it is generally acceptable if the product being surfaced is more or less evenly fed across the width of the machine.
As indicated above, the practice of feeding workpieces evenly is essential in order to distribute wear of machine components in addition to abrasive belts, such as conveyor belts, conveyor belt support beds, hold-down shoes, pinch rolls, contact drum surfaces and the like. It is also desirable to achieve uniform wear of other surface treating or surfacing components such as knife cutter heads, brushes, buffs, or any other finishing or abrading-type tooling used on these machines. The term xe2x80x9cabrasive beltsxe2x80x9d as employed herein is utilized in a comprehensive sense, and is intended to include those other moving surface treating components including knife cutter heads, brushes, buffs, or any other type tooling used on these machines.
It has been a long term and widely recognized problem throughout the industry that the seemingly simple task of evenly feeding workpieces or products across the width of a machine is difficult to achieve, and in certain instances, even more difficult to manage. Because of the nature of the individual operations or tasks, machine operators generally prefer to feed products in-line and management personnel and/or supervisors have no practical way to monitor this function so as to ascertain that even or uniform feeding of workpieces is being achieved. The width utilization system of the present invention will not only prompt an operator to evenly feed workpieces across the width of a machine, but will additionally provide supervisory personnel with the means to monitor individual operator performance as it relates to workpiece feed practices.
Briefly, and in accordance with the present invention, a width utilization prompter/monitor system is provided for use in combination with wide-belt abrasive surface treating apparatus or systems. Wide-belt abrasive surface treating apparatus typically are provided with a frame which supports a conveyor with drive means for moving an endless belt in a drive direction along a defined path, with the belt accordingly having a top flight for transporting individual workpieces along a drive axis between an infeed and a discharge end. One or more workpiece treating stations are operationally positioned between the ends, with the workpiece treating station defining a wide abrading station. Typically, a wide abrasive belt or similar surface treating mechanism is disposed in one or more workpiece treating station with other devices such as, for example, rotary knife cutter heads, brushes, buffs, or other surface finishers being provided as required. Each workpiece treating station is superimposed adjacent the top flight and positioned to contact the surface of workpieces being transported along the conveyor top flight.
The width use monitor system of the present invention comprises an array consisting of a plurality of axially spaced apart signal generating workpiece sensors, with these sensors being disposed in axially spaced apart relationship across the width of the machine, preferably transversely to the drive axis. Each sensor creates a signal in response to the presence of a workpiece moving along a certain discrete or predetermined transverse segment of the conveyor belt. A readout means such as a data processor system is provided for receiving signals from each sensor in the array, with the readout means including a readout indicator or information display. The data processor operatively responds to the signals generated by the sensors and the resultant information is displayed on an information display panel. The data processing means are coupled between the sensors and the readout means or information panel, and evaluates and determines the accumulative duration of time or a lineal measurement during which the presence of a workpiece is detected by each of the individual sensors comprising the array. By accumulating this information, the data processing means determines which individual sensor in the array has detected the shortest or lowest cumulative amount of time or length. Thus, the data processing means is adapted to compare the duration of these cumulative measurements for which workpieces were detected by each of the individual sensors in the array relative to that certain sensor detecting the shortest duration of cumulative measurement.
In this arrangement, each individual lane across the width of the belt is provided with its individual array of lights, including green, yellow and red lights. The green light, when illuminated, indicates to the operator that the individual lane is safe and appropriate for material feed. Upon further usage, the green indicator light may be extinguished and the yellow light illuminated. Illumination of the yellow light indicates that the operator should utilize caution and use efforts to avoid feeding product through that lane. Upon further non-equal utilization, the yellow light may be replaced by the red light for that lane, with the red light indicating that the operator should interrupt feeding product down that lane entirely and utilize alternate lanes. The monitor system may be reset from time to time by supervisory personnel, thus enabling the personnel to monitor belt utilization during given work periods.
As an alternative to utilization of the lowest usage lane as a reference, the data processing means may be adapted to detect which sensor in the array has the greatest duration of cumulative measurement of workpiece exposure. These extremes of cumulative exposure may be referred to as the xe2x80x9cthe range limitxe2x80x9d, and hence the term xe2x80x9crange limitxe2x80x9d is used in a comprehensive sense, and is intended to define one or the other of the extremes, either the greatest duration or the least duration. Additionally, the readout means are designed to indicate the differences in cumulative measurements for each sensor in the array relative to that certain sensor representing the extreme range limit of measurement, such as the shortest duration of cumulative measurements. The readout means are provided with a reset feature which is controlled by supervisory personnel in order to enable monitoring of performance during given work periods.
As an added feature of the present invention, the data processing means may include an input representing the conveyor rate of speed for determining the aggregate length of the individual workpieces which have been transported along the top flight and detected by the sensors over any desired period or interval of time. This feature advantageously provides information useful in determining when an individual abrasive belt or surface contacting member such as a knife cutter head is reasonably in need of replacement. In order to display the information responsive to the processing of the aggregate length of individual workpieces, this total exposure time representing the work history of an individual sanding head may be advantageously displayed on a separate indicating panel, with the displayed information typically being representative of the greatest amount of work exposure. Thus, the work exposure can be advantageously represented as the history of that certain lane undergoing the greatest exposure to workpieces.
Therefore, it is a primary object of the present invention to provide an improved system for monitoring the operation of a workpiece surfacing component such as a wide abrasive belt so as to enhance uniform distribution of wear across the transverse width of the surfacing component.
It is yet a further object of the present invention to enhance the uniform utilization of a wide surface treating system such as an abrasive belt system wherein an array of individual axially spaced apart sensors are utilized to sense workpiece presence and thereby indicate the extent to which certain width segments of the apparatus have been exposed to contact with workpieces and to assist in uniform distribution of wear.
It is a yet a further object of the present invention to provide an improved monitor system for use with wide-belt abrasive surface treating apparatus wherein an array of individual axially spaced apart workpiece sensors are provided to gather data relating to the history of distribution of workpieces across the width of a conveyor-fed wide abrasive surface treating apparatus.
Other and further objects of the present invention will become apparent to those skilled in the art upon a study of the following specification, appended claims, and accompanying drawings.